The invention relates generally to a pumped storage facility, and more specifically to a pumped storage facility that includes other features that cooperate with the pumped storage facility to make it economically feasible to construct and operate the facility.
The availability of power when needed is a major drawback to the production and use of any form of energy, but particularly alternative energy. The requirement that one match the inconsistent availability of alternative energy-produced power with production from a standard power plant, or Guaranteed Source of Power (“GSOP”), is also a disadvantage. A GSOP is typically a coal-burning power plant, nuclear energy plant, natural gas burning plant, or any other conventional energy-producing source of power.
If the wind is blowing or the sun is shining, alternative power is available if one has windmills or photovoltaic cells in operation. However, if the blowing wind or the shining sun stops abruptly, a GSOP must be operating to meet demand that typically does not start or stop abruptly. When the GSOP is operating and the wind-based or sun-based power production facilities start producing, there is a dilemma about what to do with excess power being produced. The energy provider must decide whether to slow power production from the GSOP with the risk that the alternative source may suddenly slow or stop altogether, or maintain production and waste energy.
Pumped storage facilities are currently used to help balance production with demand, especially during peak power demand periods on very hot days (when cooling power demands are highest) and very cold days (when heating power demands are highest). Pumped storage facilities have reservoirs, such as ponds or lakes, at two different elevations, and the ponds or lakes are connected to one another through one or more large pipes or other water-conveying structures through or over which water can flow or be pumped. Rather than shutting a power plant down completely when demand for power production is small, excess power can be used to pump water from the lower reservoir to the upper reservoir. When demand for power climbs, the power used to run the pumps is reduced to accommodate the demand. At a higher level of demand for power, water is no longer pumped. Finally, when demand increases further, water can be released to flow from the upper reservoir through a hydroelectric transducer to produce electricity to meet the higher demand. If demand subsequently drops, the flow of water that produces energy can be halted. At any time that demand falls below GSOP power production, any excess power generated by the GSOP can be diverted into pumping water from the lower pond into the upper pond. Thus, hydroelectric power production supplements conventional energy sources by using a two-pond system to “store” and “release” the potential energy of water stored at elevation as needed. As the GSOP is no longer able to keep up with demand, a clean source of power supplies the energy demand. If demand abruptly or temporarily drops, this power is abruptly or temporarily diverted into pumping water from the lower pond into the upper pond.
If a pumped storage facility can balance the “peaks and valleys” of the multiple sources of clean power production against the fluctuating demand during the daily cycle, then the GSOP can operate at its most efficient rate, and power supply can be matched to public demand. However, because the construction costs for typical pumped storage facilities are substantial, most pumped storage facilities rely on a natural source of water, such as a river or a lake, to supply the water. This restricts the available sites for the facility. The need therefore exists for a pumped storage facility design that can be incorporated into virtually any geographic or demographic area.